rigidbodies not working with a lot of objects
This last cube is not part of the same Rigid Body World collection, so remove the second collection, add a new one, and choose RigidBodyWorld instead of RigidBodyWorld.011:

RigidBodyWorld is a kind of ghost collection that is created and selected by default in the Scene panel &gt; Rigid Body World when you create a rigid body object, more explanations give here by Blender Frenzy. You can also put your rigid body objects in a real outliner collection if you want, in this case, select it in the Scene panel: